Projector for photographic transparencies

ABSTRACT

A slide projector wherein the slide changer carries a two-armed lever which tends to resist pivotal movement and rotates a wheel to thereby index the magazine for slides while the slide changer continues to move upon completed return of a slide into the respective compartment. An adjustable selector can pivot the lever from a neutral position to one of two operative positions in which the lever respectively rotates the wheel in a clockwise and in a counterclockwise direction (forward and backward transport of the magazine). A resetting member pivots the lever to neutral position upon completion of each indexing step. The selector cooperates with cam faces on one arm and the resetting member cooperates with extensions on the other arm of the lever.

iinited States Patent Fleissner Sept. 12, 1972 [72] Inventor: JosefFleissner, Kirchseeon, Germany [73] Assignee: Afga-GevaertAktiengesellschaft,

1 Leverkusen, Germany [22] Filed: March 20, 1970 [21] Appl. No.: 21,417

[30] Foreign Application Priority Data March 21, 1969 Germany ..G 6911413.2

[52] US. Cl ..353/103 [51] Int. Cl. ..G03b 23/00 [58] Field of Search..353/103-117; 40/79; 74/891,422

[5 6] References Cited UNITED STATES PATENTS 3,165,971 1/1965 Zillmer..40/79 3,059,360 10/1962 Krauskofi ..353/116 3,473,871 10/1969 Hofmann..353/116 Primary Examiner-Leonard Forman Assistant Examiner-A. J.Mirabito AttorneyMichael S. Striker [5 7] ABSTRACT A slide projectorwherein the slide changer carries a two-armed lever which tends toresist pivotal movement and rotates a wheel to thereby index themagazine for slides while the slide changer continues to move uponcompleted return of a slide into the respective compartment. Anadjustable selector can pivot the lever from a neutral position to oneof two operative positions in which the lever respectively rotates thewheel in a clockwise and in a counterclockwise direction (forward andbackward transport of the magazine). A resetting member pivots the leverto neutral position upon completion of each indexing step. The selectorcooperates with cam faces on one arm and the resetting member cooperateswith extensions on the other arm of the lever.

9 Claims, 3 Drawing Figures PATENTEDSEP 12 me 3.690.186

Fig. Fig. 3

INVENTOR. JOSEF FLEISSNER a-m/ r- 1A4,- 4'60r 11) PROJECTOR FORPHOTOGRAPI-IIC TRANSPARENCIES BACKGROUND OF THE INVENTION particularlyto improvements in projectors of the type wherein the-slide changereffects stepwise forward or rearward indexing of the magazine for slidesin response to movement of a slide from projection posil tion back intothe corresponding compartment of the magazine.

In certain presently known slide projectors of the just outlined type,the slide changer carries a pivotable displacing arm which is biased toa neutral position and includes a follower which can track the groove ofan adjustable cam so as to index the magazine forwardly or backwards,depending on the position of the cam. Since the arm is permanentlybiased to neutral position, the length of grooves in the cam must besuch that the follower is positivelyguided during the entire returnstroke of the slide changer. Therefore, such slide changers do notpermit manual displacement of the magazine at a time when the slidechanger dwells in that position in which it is ready totransport a freshslide into registry with the optical system of the projector;

SUMMARY OF THE INVENTION An object of the invention is to provide aslide projector wherein a circular or elongated slide magazine can berotated or moved lengthwise independently of the slide changer when thelatter is ready to transport a slide to projection position.

Another object of the invention is to provide a slide projector with anovel indexing mechanism for the magazine and with novel means forselecting the direction of movement of the magazine in response tomanipulation of the slide changer.

A further object of the invention is to provide a projector wherein theslidechanger can be moved back and forth without causing movements ofslides to and I from positions of registry with the optical system.

prises a slide changer movable between first and second positions, anindexible member arranged to move the magazine forwardly or backwards inresponse to rotation in first and second directions, a displacing membermounted on the slide changer for movement in response to application ofa predetermined minimum force between a first operative position inwhich it rotates the indexible member in the first directioma neutralposition in which it bypasses the indexible member, and a secondoperative position in which it rotates the indexible member in thesecond direction in response to movement of the slide changer, selectormeans which is adjustable to effect movement of the displacing member toa desired one of its operative positions in response to movement of theslide changer, and resetting means for moving the displacing member toneutral position in response to movement of the slide changer.

The arrangement is preferably such that the displacing member firstengages with and is moved to one of its operative positions by theselector means, that the 0 displacing member thereupon rotates theindexing member in the desired direction, and that the displacing memberthereupon engages with and is moved to neutral position by the resettingmeans in response to movement of the slide changer in a direction toreturn a slide into the corresponding compartment of the magazine.

The novel features which are considered a characteristic of theinvention are set forth in particular in the appended claims. Theimproved projector itself, however, both as to its construction and itsmode of operation, together with additional features and advantagesthereof, will be best understood upon perusal of the following detaileddescription of certain specific embodiments with reference to theaccompanying drawing.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a fragmentary partlyelevational and partly sectional view of certain details in a slideprojector DESCRIPTION OF THE PREFERRED EMBODIMENTS The drawingillustrates a portion of a projector having a housing 1 which supportsor accommodates an indexible magazine or tray M for photographictransparencies or slides (not shown). The means for indexing themagazine M in a clockwise or counterclockwise direction comprises ashaft 2 which is rotatably journalled in the housing 1 and carries anindexing member or wheel 3 provided with a set of equidistant axiallyparallel indexing projections or pins 4. The shaft 2 further carries agear 102 which meshes with a gear provided on the magazine M. In theillustrated embodiment, the magazine is a rotary trayhaving radiallyextending slide compartments, but it is equally possible to employ thegear 102 as a means for moving a straight magazine with parallelcompartments for slides.

The means for rotating the wheel 3 comprises a reciprocable slidechanger 6 and a displacing member here shown as a two-armed lever 8which is secured to the slide changer by a pivot pin 7 so that it canturn in a plane which is parallel to the plane of the wheel 3. The slidechanger 6 is movable between a first position in which it maintains aslide in registry with the optical system of the projector so that theimage of such slide is visible on a screen, and a second position inwhich the slide is returned into the corresponding, compartment of themagazine M. The direction in which the slide changer 6 moves from firstto second position is indicated by arrow A.

The lever 8 has a first arm 8a which carries a motion transmitting block8b serving to cooperate with the pins 4 and provided with two notches8c, 8d. The arm 8a is further provided with two mirror symmetrical camfaces 8e 8f which can cooperate with cam faces 9a, 9b of an adjustableselector 9. The latter is provided with a manually movable adjustingknob and is mounted in the housing 1 in such a way that it requires acertain force to move it between two spaced positions including the oneshown in FIGS. 1-2 and another in which the cam faces 9a, 9b are locatedto the left of the positions shown in FIGS. 1-2. The means for producingfriction between the housing 1 and selector 9 may include a suitablespring, elastic cushion or the like. A spring 7a or the like is providedto oppose accidental pivotal movement of the lever 8 about the axis ofthe pivot 7, i.e., the lever 8 and selector 9 respectively tend toresist movement with reference to the slide changer 6 and housing 1.

The second arm 8g of the lever 8 is provided with two portions orextensions 8h, 8k which can engage the adjacent guide faces 11b, 110 ofa plate-like resetting member 11 adjacent to the slide 9. The resettingmember 11 has an aperture lla which registers with the aperture of theselector 9 (such aperture is flanked by the cam faces 9a, 9b). Theaperture 11a is flanked by the guide faces 1 1b, 110. The apertures ofthe selector 9 and resetting member 11 permit unimpeded reciprocatorymovements of the slide changer 6.

The projector is further provided with a detent means for yieldablyholding the indexing wheel 3 in such positions in which the slides inselected compartments of the magazine M are located in the path ofmovement of the slide changer 6. Such detent means includes aspring-biased pawl 12 whose pallet normally extends into the spacebetween and engages with the two adjoining pins 4.

The Operation:

FIGS. 1 and 2 illustrate the selector 9 in a position in which it causesthe lever 8 to rotate the wheel 3 in a clockwise direction as indicatedby the arrow B (forward transport of the magazine M). When the slidechanger 6 is moved in the direction of arrow A to transport a slide backinto the corresponding compartment of the magazine M, the cam face 82 onthe arm 8a engages the cam face 9a of the selector 9 and causes thelever 8 to pivot in a counterclockwise direction so that the notch 8dmoves toward engagement with the adjacent pin 4' (located to the rightof the section line IIIllI shown in FIG. 2). Further movement of theslide changer 6 in the direction of arrow A (after the slide is returnedinto the corresponding compartment) causes the block 8b to rotate thewheel 3 in a clockwise direction whereby the wheel displaces the detentpawl 12 and places the next slide into registry with the slide changer6. Just before the slide changer 6 completes its movement in thedirection of arrow A, the extension 8h engages the adjacent guide face11b of the resetting member 11 and pivots the lever 8 in a clockwisedirection so that the block 8b is disengaged from the pin 4. The palletof the detent pawl 12 snaps into the space between the adjoining pins 4and holds the wheel 3 in an angular position in which the next slide isready to be withdrawn from its compartment as soon as the slide changer6 beings its movement in the opposite direction.

The selector 9 is movable to a median or ineffective position in whichthe block 8b can bypass the pins 4 when the slide changer 6 moves in thedirection indicated by arrow A. The slide changer 6 is then ineffectiveand cannot transport slides to and from the position of registry withthe optical system.

FIG. 2 illustrates the wheel 3 in the new angular position (consider thepositions of pin 4' in FIGS. 1 and 2). Further movement of slide hanger6 in the direction of arrow A causes the guide face 1 lb and extension8h to pivot the lever 8 so that the block 8b is disengaged from the pin4'. This enables the operator to index the magazine M at will while theslide changer 6 dwells in its second position. Return movement of theslide changer 6 to first position causes the resetting member 11 topivot the lever 8 clockwise so that the cam face 8e reengages the camface 9a when the slide changer 6 performs the next movement in thedirection of arrow A. This insures that the notch 8d engages the nextpin 4" and indexes the wheel 3 in a clockwise direction.

If the magazine M is to be moved rearwardly, the operator manipulatesthe knob 10 to move the selector 9 in a direction to the left, as viewedin FIG. 1 or 2, so that the cam face 8f cooperates with the cam face 9band the block 8b rotates the wheel 3 in a counterclockwise directionwhenever the slide changer 6 moves in the direction of arrow A.

The selector 9 replaces the conventional grooved cam which guides thefollower of the displacing member in presently known slide projectors.It will be seen that the selector 9 engages with the lever 8 only duringa relatively short stage of movement of the slide changer 6 toward theposition in which the slide changer is ready to withdraw a fresh slide.The spring 7a insures that a predetermined minimal force must be appliedin order to move the lever 8 between its neutral position and the twooperative positions. Thus, the lever 8 does not tend to move toward itsneutral position; such movement is effected by the guide face 11b or 110of the resetting member 11 while the lever 8 continues to move in thedirection indicated by the arrow A. The arrangement is such that, whenthe slide changer 6 is moved to return a slide into the magazine M, thecam face 8e or 8f engages the cam face 9a or 9b to pivot the lever 8 toone of its operative positions, the notch 8d or then engages with a pin4 to rotate the wheel 3 and to index the magazine M when the slidereturns into its compartment, and that the extension 8h or 8k thereuponengages the guide face 11b or llc to return the lever 8 to neutralposition in which the block 8b permits manual indexing and/or insertionor withdrawal of the magazine M against the opposition of the springwhich biases the detent pawl 12. The block 8b is then located within thearea surrounded by the pins 4.

When the slide changer 6 is moved upwardly from the position shown inFIG. 2, the cam face 8e clears the cam face 9a but the right-handportion of the enlarged lower end of the arm 80 engages the resettingmember 11 (at the right-hand side of the aperture 11a) to pivot thelever 8 in a clockwise direction so that the arm 8a can pass through theaperture 11a. When the slide changer 6 again moves in the direction ofthe arrow A, the lower end of the arm 8a can pass through the aperture11a but the cam face 8e engages the cam face 9a (which is nearer to thecenter of the aperture 11a )and pivots the lever 8 back to the operativeposition shown in. FIG. 1. Further downward movement of the slidechanger 6 then causes the wheel 3 to rotate in the direction indicatedby the arrow B. The magazine M can be indexed against the oppositionofthe pawl 12 when the slide changer 6 is in the upper end position,

i.e., when the arm 8 a of the lever 8 is located above the aperture inthe selector 9. When the lower end of the arm 8a passes through theaperture 11a the lever 8 is at least substantially parallel to the slidechanger 6.

Without further analysis, the foregoing will so fully reveal the gist ofthe present invention that others can, by applying current knowledge,readily adapt it for various applications without omitting featureswhich fairly constitute essential characteristics of the generic andspecific aspects of my contribution to the art and, therefore, suchadaptations should and are intended to be comprehended within themeaning and range of equivalence of the claims.

' What is claimed as new and desired to be protected by Letters Patentis set forth in the appended claims:

1. In a projector for slides which are stored in an indexible magazine,a combination comprising a slide changer movable in at least one firstdirection between first and second positions; a rotary indexible memberhaving an axis of rotation and arranged to move the magazine forwardlyand backwards in response to rotation of said indexible member aboutsaid axis. in first and second directions; a displacing member mountedon said slide changer for movement in at least one second direction withreference to said slide changer in response to the application of apredetermined minimum force between a first operative position in whichit rotates said indexible member in said first direction, a neutralposition in which it bypasses said indexible member, and a secondoperative position in which it rotates said indexible member in saidsecond direction in response to movement of said slide changer, saiddisplacing member being arranged to share the movements of said slidechanger in said first direction; selector means adjustable to effect themovement of said displacing member to a desired one of said operativepositions by applying said force to said displacing member in responseto movement of said slide changer; resetting means located in the pathof movement of said displacing member and arranged to move saiddisplacing member to said neutral position in response to movement ofsaid slide changer; and means for mounting said displacing member onsaid slide changer so that said displacing member normally tends tomaintain any one of said positions thereof with reference to said slidechanger.

2. In a projector for slides which are stored in an indexible magazine,a combination comprising a slide changer movable in at least onedirection between first and second positions and through an intermediateposition and being arranged to transport a slide into the magazineduring movement from said first to said intermediate position; a rotaryindexible member having an axis of rotation and arranged to move themagazine forwardly and backwards in response to rotation of saidindexible member about said axis in first and second directions; adisplacing member comprising a lever pivotable on said slide changer inresponse to the application of a predetermined minimum force between afirst operative position in which it rotates said indexible member insaid first direction during movement of said slide changer from saidintermediate toward said second position thereof, a neutral position inwhich it bypasses said indexible member, and a second operative positionin which it rotates said indexible member in said second direction inresponse to movement of said slide changer from said intermediate tosaid second position thereof, said lever being arranged to share themovement of said slide changer in said one direction and having a firstarm comprising two first cam faces and a second arm comprising first andsecond portions; selector means adjustable to effect the movement ofsaid lever to a desired one of said operative positions by applying saidforce to said lever in response to movement of said slide changer fromsaid first position, said selector means comprising two second cam facesand being movable to a first position in which one of said second camfaces cooperates with one of said first cam faces to move to said leverto said first operative position and said selector means being furthermovable to a second position in which the other of said second cam facescooperates with the other of said first cam faces to move said lever tosaid second operative position; and resetting means located in the pathof movement of said lever and arranged to move said lever to saidneutral position, said resetting means comprising first and second guidefaces respectively engaging said first and second portions of saidsecond arm to effectthe movement of said lever to said neutral positionwhen said slide changer moves from said intermediate toward said secondposition thereof and said lever respectively dwells in said first andsecond operative positions.

3. A combination as defined in claim 1, wherein said selector means isarranged to move said displacing member to selected operative positiononly during movement of said slide changer from said first toward saidsecond position, said slide changer being arranged to withdraw slidesfrom the magazine during movement from said second toward said firstposition thereof.

4. A combination as defined in claim 1, wherein said resetting means isprovided with an aperture for said slide changer and for said displacingmember in the neutral position of said displacing member.

5. A combination as defined in claim 1, wherein said displacing membercomprises a lever which is pivotable with reference to said slidechanger, said lever having a first arm which cooperates with saidselector means and a second arm cooperating with said resetting means.

6. A combination as defined in claim 5, wherein said first arm comprisestwo first cam faces and said selector means comprises two second camfaces, said selector means being movable to a first position in whichone of said second cam faces cooperates with one of said first cam facesto move said displacing member to first operative position, and to asecond position in which the other second cam face cooperates with theother first cam face to move the displacing member to said secondoperative position in response to movement of said slide changer.

7. A combination as defined in claim 1, wherein said selector means isadjustable transversely of said slide changer and is provided withmanually operable adjusting means.

indexing member comprises a wheel having a plurality of equidistantprojections one of which is located in the path of movement of saiddisplacing member whenever the latter dwells in one of said operativepositions and while said slide changer moves from said first toward saidsecond position thereof.

1. In a projector for slides which are stored in an indexible magazine, a combination comprising a slide changer movable in at least one first direction between first and second positions; a rotary indexible member having an axis of rotation and arranged to move the magazine forwardly and backwards in response to rotation of said indexible member about said axis in first and second directions; a displacing member mounted on said slide changer for movement in at least one second direction with reference to said slide changer - in response to the application of a predetermined minimum force - between a first operative position in which it rotates said indexible member in said first direction, a neutral position in which it bypasses said indexible member, and a second operative position in which it rotates said indexible member in said second direction in response to movement of said slide changer, said displacing member being arranged to share the movements of said slide changer in said first direction; selector means adjustable to effect the movement of said displacing member to a desired one of said operative positions by applying said force to said displacing member in response to movement of said slide changer; resetting means located in the path of movement of said displacing member and arranged to move said displacing member to said neutral position in response to movement of said slide changer; and means for mounting said displacing member on said slide changer so that said displacing member normally tends to maintain any one of said positions thereof with reference to said slide changer.
 2. In a projector for slides which are stored in an indexible magazine, a combination comprising a slide changer movable in at least one direction between first and second positions and through an intermediate position and being arranged to transport a slide into the magazine during movement from said first to said intermediate position; a rotary indexible member having an axis of rotation and arranged to move the magazine forwardly and backwards in response to rotation of said indexible member about said axis in first and second directions; a displacing member comprising a lever pivotable on said slide changer - in response to the application of a predetermined minimum force - between a first operative position in which it rotates said indexible member in said first direction during movement of said slide changer from said intermediate toward said second position thereof, a neutral position in which it bypasses said indexible member, and a second operative position in which it rotates said indexible member in said second direction in response to movement of said slide changer from said intermediate to said second position thereof, said lever being arranged to share the movement of said slide changer in said one direction and having a first arm comprising two first cam faces and a second arm comprising first and second portions; selector means adjustable to effect the movement of said lever to a desired one of said operative positions by applying said force to said lever in response to movement of said slide changer from said first position, said selector means comprising two second cam faces and being movable to a first position in which one of said second cam faces cooperates with one of said first cam faces to move to said lever to said first operative position and said selector means being further movable to a second position in which the other of said second cam faces cooperates with the other of said first cam faces to move said lever to said second operative position; and resetting means located in the path of movement of said lever and arranged to move said lever to said neutral position, said resetting means comprising first and second guide faces respectively engaging said first and second portions of said second arm to effect the movement of said lever to said neutral position when said slide changer moves from said intermediate toward said second position thereof and said lever respectively dwells in said first and second operative positions.
 3. A combination as defined in claim 1, wherein said selectOr means is arranged to move said displacing member to selected operative position only during movement of said slide changer from said first toward said second position, said slide changer being arranged to withdraw slides from the magazine during movement from said second toward said first position thereof.
 4. A combination as defined in claim 1, wherein said resetting means is provided with an aperture for said slide changer and for said displacing member in the neutral position of said displacing member.
 5. A combination as defined in claim 1, wherein said displacing member comprises a lever which is pivotable with reference to said slide changer, said lever having a first arm which cooperates with said selector means and a second arm cooperating with said resetting means.
 6. A combination as defined in claim 5, wherein said first arm comprises two first cam faces and said selector means comprises two second cam faces, said selector means being movable to a first position in which one of said second cam faces cooperates with one of said first cam faces to move said displacing member to first operative position, and to a second position in which the other second cam face cooperates with the other first cam face to move the displacing member to said second operative position in response to movement of said slide changer.
 7. A combination as defined in claim 1, wherein said selector means is adjustable transversely of said slide changer and is provided with manually operable adjusting means.
 8. A combination as defined in claim 1, wherein said slide changer is reciprocable between said first and second positions and said displacing member is arranged to engage first with said selector means, thereupon with said indexible member and finally with said resetting means in response to movement of said slide changer from first toward second position.
 9. A combination as defined in claim 1, wherein said indexing member comprises a wheel having a plurality of equidistant projections one of which is located in the path of movement of said displacing member whenever the latter dwells in one of said operative positions and while said slide changer moves from said first toward said second position thereof. 